1. Field of the Invention
This invention relates to a set of fastening means, such as a sheet of staples contiguously arranged in a row which are to be loaded in a manual or electric stapler or a clip belt consisting of metallic clips arranged like a belt which are used to fasten layers of, for example, paper together.
2. Description of the Related Art
Nowadays, there is on the market a copying machine provided with an electric stapler so that a fixed number of sheets of paper onto which an original work has been copied are not mingled with another fixed number of copied sheets when all the sheets are placed in layers by means of, for example, a sorter.
Above an edge of the sheets placed in layers, a magazine of the electric stapler is disposed which is loaded with a plurality of sets of staples arranged in rows, and, under the edge of the sheets, a clincher of the electric stapler is disposed which clinches both ends of the staple interrelatedly with the magazine.
The magazine is provided with a pushing plate for separating a staple occupying the front row of the set of staples from the other staples of the set of staples and then pushing out the front staple. With the layers of paper between the magazine and the clincher, the pushing plate is pressed against the set of staples perpendicularly so as to push out the front staple. The front staple which has been pushed out and separated from the other staples of the set of staples by means of the pushing plate is bent into a U-shape, and then both ends of the U-shaped staple are driven into the layers of paper. When both the ends of the staple project from the bottom of the layers of paper, the clincher approaches the pushing plate and clinches the ends thereof so as to fasten the layers of paper together.
Conventionally, a set of staples of this type are formed by sticking a film via an adhesive agent to the staples arranged in a row. A straight staple 1 occupying the front row of the set of staples is driven out and is formed into a U-shape consisting of leg portions 2, 2 and a straight middle portion 3, as shown in FIG. 11. Films 4 stuck to the top and back sides of the middle portion 3 of the staple 1 are so thin as to be cut off with slight force when the staple 1 is driven out.
However, the conventional set of staples have a problem in that a part of the film 4 stretches out from one or both sides of the staple 1 in a thickness direction of the staple 1 when the staple 1 is pushed out and separated from the other staples of the set of staples by means of the pushing plate. This staple 1 is inferior in outward appearance.
Further, the conventional set of staples have a problem in that high driving power or large driving mechanism is required because great force is required to separate a staple from the other staples of the set of staples. Accordingly, in order to enlarge the pushing force of the pushing plate, the weight of the pushing plate must be enlarged, or the input acceleration required when the pushing plate is pushed out must be increased.